Field of the Invention
The present invention relates to an antenna element, and, in particular, to a structure of a surface-mount multi-resonant antenna element. The present invention also relates to an antenna device using the antenna element, and wireless communication equipment using the antenna device.
Description of Related Art
In recent years, a wireless mobile terminal, such as a cellular telephone, has many functions, such as a global positioning system (GPS), Bluetooth (registered trademark), and a wireless LAN, and becomes multi-functional for communication. With a wireless mobile terminal having multiple functions for communication, need for a multi-resonant antenna has been increasing. In general, a multi-resonant antenna can constitute dual bands or multiple bands antenna by using a plurality of radiation conductors having different antenna lengths. For example, Japanese Patent Application Laid-Open No. 2004-186730 discloses a multi-resonant antenna, in which a radiation conductor on a high frequency side and a radiation conductor on a low frequency side are connected to an inductor element having a meander pattern.
Although not being so small as compared to a linear antenna, a conventional multi-resonant antenna can contribute to reduction in size as an antenna for a wireless mobile terminal as large as a cellular telephone. However, since the conventional multi-resonant antenna is too large for even smaller equipment, such as wearable equipment which is available in recent years, further reduction in size has been demanded.